1. Field of the Invention
The present invention relates to a high-definition picture signal recording apparatus for recording a high-definition picture signal of which an amplitude level is controlled, a high-definition picture signal reproducing apparatus for reproducing a high-definition picture signal of which an amplitude level is controlled, and a high-definition picture signal recording/reproducing apparatus for recording and reproducing a high-definition picture signal of which an amplitude level is controlled. Also, the present invention relates to picture signal recording method and apparatus for recording not only a high-definition picture signal but also a normal picture signal. In addition, the present invention relates to a picture signal recording apparatus for recording a picture signal such as a normal picture signal or a high-definition picture signal by determining a recording mode in dependence on a type of the picture signal and a high-definition picture signal reproducing apparatus for reproducing the picture signal recorded with the high-definition picture signal recording apparatus by distinguishing the recording mode.
2-1. A First Related Art
A broad-band type of high-definition picture signal such as a high-vision signal (hereinafter, called an HD picture signal) and an extended definition television signal (hereinafter, called an EDTV signal) have been recently known. The number of horizontal scanning lines in a frame of picture image displayed with the high-definition picture signal is higher than that in a frame of picture image displayed with a conventional picture signal such as a national television system committee (NTSC) type of signal. In an apparatus utilizing the high-definition picture signal, the signal is digitized to perform various types of digital processing for a digital signal. Therefore, because a dynamic range of the digital signal is strictly limited to perform the digital processing, it is required to control all amplitude level of the high-definition picture signal.
To control the amplitude level of high-definition picture signal in a conventional method, a synchronizing signal is synchronized with the high-definition picture signal, an amplitude level of the synchronizing signal is detected, and the amplitude level of the high-definition picture signal is controlled according to the amplitude level of the synchronizing signal. However, the high-definition picture signal is often processed according to various types of digital processing in an apparatus utilizing the high-definition picture signal while deleting a part of the high-definition picture signal transferred in vertical blanking periods and horizontal synchronizing signal periods to minimize a capacity of memories for storing the high-definition picture signal. Therefore, in cases where the amplitude level of the high-definition picture signal is corrected according to the amplitude level of the synchronizing signal, there is a drawback that the correction of the amplitude level is not accurate.
To solve the drawback, a level standard signal adding apparatus in which a level standard signal is added to one of horizontal scanning lines to which a high-definition picture signal is allocated and a high-vision signal to which the level standard signal is added have been proposed by this applicant.
Also, an amplitude level correcting apparatus in which an amplitude level of a high-definition picture signal is corrected according to a level standard signal has been proposed by this applicant.
2-2. Problems of the First Related Art to be Solved by the Present Invention
However, a high-definition picture signal is recorded with a recording/reproducing apparatus while deleting a part of the high-definition picture signal allocated to peripheral horizontal scanning lines placed at upper and lower peripheral portions of an image plane. In this case, the level standard signal cannot be recorded in a recording medium of the recording/reproducing apparatus because of the deletion of the level standard signal even though the level standard signal is added to the peripheral horizontal scanning lines. Therefore, even though the high-definition picture signal is recorded and reproduced with the recording/reproducing apparatus after the amplitude level of the high-definition picture signal is corrected in a level correcting apparatus provided in a recording section of the recording/reproducing apparatus, there is a drawback that an amplitude level error of the high-definition picture signal generated in the recording/reproducing apparatus cannot be eliminated.
Also, in cases where an information signal is multiplexed in the level standard signal, there is another drawback that the information signal is undesirably deleted because of the deletion of the level standard signal.
2-3. A Second Related Art
A so-called UNIHI (a registered trademark) type of high-vision video tape recorder (VTR) has been well-known as a magnetic recording/reproducing apparatus for recording/reproducing a high-definition picture signal which has a wider frequency band than that of a normal picture signal conventionally utilized and has a larger number of scanning lines than that of the normal picture. In the high-vision VTR, a pair of color difference signals belonging to a high-definition picture signal are respectively converted in order of scanning lines to produce a plurality color difference line signals, and the color difference line signals are respectively time-compressed to produce a plurality of compressed color difference line signals. In this case, because the number of scanning lines in the high-definition picture signal is too high to record the color difference line signals, the color difference line signals are thinned out on every other scanning line to reduce the number of color difference line signals time-compressed. Also, a luminance signal belonging to a high-definition picture signal is time-compressed to produce a compressed luminance signal. Thereafter, the compressed color difference line signals and the compressed luminance signal are unified according to a time-division multiplexing to produce a time compressed integration (TCI) signal, and the TCI signal is recorded and reproduced to/from an information recording medium such as a magnetic tape.
The reason that the color difference line signals are thinned out on every other scanning line is that a quality of picture image displayed in a displaying unit according to the high-definition signal reproduced is not degraded so much.
2-4. Problems of the Second Related Art to be Solved by the Present Invention
However, In cases where not only a high-definition picture signal but also a normal picture signal conventionally utilized are recorded and reproduced to/from an information recording medium in the high-vision VTR, the normal picture signal is also thinned out on every other scanning line. As a result, there is a drawback that a quality of picture image displayed in a displaying unit according to the normal picture signal reproduced is considerably degraded because the number of scanning lines in the normal picture signal is low.
2-5. A Third Related Art
In a conventional picture signal magnetic recording and reproducing apparatus, there are two types of recording mode in cases where a picture signal is recorded and reproduced according to a S-VHS (a registered trademark) method. One of the recording modes is a normal recording mode in which a picture signal is recorded to a normal recording medium within a normal frequency band. Also, the other recording mode is a high-performance recording mode in which a picture signal is recorded to a high-performance recording medium within a wider frequency band than the normal frequency band. Therefore, a VHS cassette in which the normal recording medium is held and a S-VHS cassette in which the high-performance recording medium is held are utilized.
The recording mode is determined in dependence on a type of recording medium loaded into the conventional picture signal magnetic recording and reproducing apparatus. Therefore, the applicant has proposed a picture signal magnetic recording and reproducing apparatus in which not only a normal picture signal such as a national television system committee (NTSC) type of signal or a phase alternation by line (PAL) type of signal but also a high-definition picture signal such as a high-vision signal (hereinafter, called an HD picture signal) or an extended definition television signal (hereinafter, called an EDTV signal) are recorded and reproduced. In the picture signal magnetic recording and reproducing apparatus proposed by the applicant, there are various recording modes such as a normal recording/reproducing mode conventionally utilized, a first recording mode in which a high-definition picture signal is recorded to a super high-performance recording medium such as a metal tape at a standard speed, a second recording mode in which a normal picture signal is recorded to the super high-performance recording medium at a low speed equal to 1/3 of the standard speed and a third recording mode in which two normal picture signals are simultaneously recorded to the super high-performance recording medium at the standard speed.
2-6. Problems of the Third Related Art to be Solved by the Present Invention
However, in the conventional picture signal magnetic recording and reproducing apparatus, the normal picture signal is limitedly processed, and the recording mode is determined according to a type of recording medium. Therefore, in cases where not only the normal picture signal but also a high-definition picture signal having a wide frequency band are processed in the conventional picture signal magnetic recording and reproducing apparatus, there is a drawback that the recording mode cannot be properly determined in the conventional picture signal magnetic recording and reproducing apparatus.